Buggy code:
public class Main extends Application { static Group root = new Group ( ) ; static AnchorPane dropTable = new AnchorPane ( ) ; static Button btnGetNpcList = new Button ( ) ; static Button btnSimulate = new Button ( ) ; static Label [ ] lblItemAmount = new Label [ 999 ] ; static ImageView [ ] newImage = new ImageView [ 999 ] ; static int [ ] item = new int [ 999 ] ; static Label lblSimulateId = new Label ( ) ; static Label lblAmount = new Label ( ) ; static Label clearBank = new Label ( ) ; static TextArea txtNpcId = new TextArea ( ) ; static TextArea txtAmountToKill = new TextArea ( ) ; static NpcDrops npc = new NpcDrops ( ) ; static ItemList itemList = new ItemList ( ) ; static NpcList npcList = new NpcList ( ) ; static int lootCount = 0 ; static Slider sldSpeed = new Slider ( ) ; private static final int HEIGHT = 500 ; @ SuppressWarnings ( "unused" ) private static final int WIDTH = 800 ; static int lastLabelPositionX = 0 ; static int labelCount = 0 ; static boolean firstLabel = true ; static int lastLabelPositionY = 10 ; static int lastPicPositionX = 0 ; static int lastPicPositionY = 32 ; static int pictureCount ; static boolean firstPicture = true ; @ Override public void start ( Stage primaryStage ) { } public static void styleLabel ( int index , int itemAmount ) { } public static void newLoot ( int index , int itemId , int amount ) { } public static void styleSlider ( ) { } public static void addPicture ( int index , int itemId ) { int newSpriteId = itemId ; if ( itemId == 995 ) { newSpriteId = 1004 ; } BufferedImage image = null ; WritableImage wr = null ; try { System . out . println ( ( "newImage:<seq2seq4repair_space>" + itemId ) ) ; <START_BUG> URL url = new URL ( ( "http:////dropsimulator.comuv.com//Sprite%20Cache//images//" + newSpriteId ) ) ; <END_BUG> image = ImageIO . read ( url ) ; wr = new WritableImage ( image . getWidth ( ) , image . getHeight ( ) ) ; PixelWriter pw = wr . getPixelWriter ( ) ; for ( int x = 0 ; x < ( image . getWidth ( ) ) ; x ++ ) { for ( int y = 0 ; y < ( image . getHeight ( ) ) ; y ++ ) { pw . setArgb ( x , y , image . getRGB ( x , y ) ) ; } } } catch ( MalformedURLException e1 ) { e1 . printStackTrace ( ) ; } catch ( IOException e ) { e . printStackTrace ( ) ; } try { if ( wr == null ) return ; Main . newImage [ index ] = new ImageView ( wr ) ; Main . item [ index ] = itemId ; if ( Main . firstPicture ) { Main . newImage [ index ] . setLayoutX ( 290 ) ; Main . newImage [ index ] . setLayoutY ( 32 ) ; Main . firstPicture = false ; } else { Main . newImage [ index ] . setLayoutX ( ( ( Main . lastPicPositionX ) + 64 ) ) ; Main . newImage [ index ] . setLayoutY ( Main . lastPicPositionY ) ; } if ( ( Main . pictureCount ) == 8 ) { Main . newImage [ index ] . setLayoutX ( 290 ) ; Main . newImage [ index ] . setLayoutY ( ( ( Main . lastPicPositionY ) + 64 ) ) ; Main . pictureCount = 0 ; } ( Main . pictureCount ) ++ ; Main . lastPicPositionX = ( ( int ) ( Main . newImage [ index ] . getLayoutX ( ) ) ) ; Main . lastPicPositionY = ( ( int ) ( Main . newImage [ index ] . getLayoutY ( ) ) ) ; Main . root . getChildren ( ) . add ( Main . newImage [ index ] ) ; Tooltip t = new Tooltip ( ( ( ( Main . itemList . getItemName ( itemId ) ) + "<seq2seq4repair_space>:<seq2seq4repair_space>" ) + ( ItemList . itemIds [ itemId ] ) ) ) ; Tooltip . install ( Main . newImage [ index ] , t ) ; t . getStyleClass ( ) . add ( "tooltip" ) ; } catch ( Exception e ) { e . printStackTrace ( ) ; } } public static void addLabel ( int index ) { } public static Color setColor ( int index ) { } public static final String formatAmount ( int j ) { } public static void addChildren ( ) { } public static void styleBankButton ( ) { } public static void styleButtonSimulate ( ) { } public static void styleTxtNpcId ( ) { } public static void styeTxtAmount ( ) { } public static void styleDropTable ( ) { } public static void styleLabelNpcToSim ( ) { } public static void styleLabelAmount ( ) { } public static void styleBtnGetNpcList ( ) { } public static void main ( String [ ] args ) { } }

Fix:
URL url = new URL ( ( ( "http:////dropsimulator.comuv.com//Sprite%20Cache//images//" + newSpriteId ) + ".png" ) ) ;